xref: /freebsd/sys/dev/psci/psci.c (revision 5bb3134a8c21cb87b30e135ef168483f0333dabb)
1 /*-
2  * Copyright (c) 2014 Robin Randhawa
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  */
27 
28 /*
29  * This implements support for ARM's Power State Co-ordination Interface
30  * [PSCI]. The implementation adheres to version 0.2 of the PSCI specification
31  * but also supports v0.1. PSCI standardizes operations such as system reset, CPU
32  * on/off/suspend. PSCI requires a compliant firmware implementation.
33  *
34  * The PSCI specification used for this implementation is available at:
35  *
36  * <http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.den0022b/index.html>.
37  *
38  * TODO:
39  * - Add support for remaining PSCI calls [this implementation only
40  *   supports get_version, system_reset and cpu_on].
41  */
42 
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
45 
46 #include "opt_acpi.h"
47 #include "opt_platform.h"
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/bus.h>
52 #include <sys/eventhandler.h>
53 #include <sys/kernel.h>
54 #include <sys/module.h>
55 #include <sys/reboot.h>
56 
57 #include <machine/bus.h>
58 #include <machine/machdep.h>
59 
60 #ifdef DEV_ACPI
61 #include <contrib/dev/acpica/include/acpi.h>
62 #include <dev/acpica/acpivar.h>
63 #endif
64 
65 #ifdef FDT
66 #include <dev/fdt/fdt_common.h>
67 #include <dev/ofw/openfirm.h>
68 #include <dev/ofw/ofw_bus.h>
69 #include <dev/ofw/ofw_bus_subr.h>
70 #endif
71 
72 #include <dev/psci/psci.h>
73 
74 struct psci_softc {
75 	device_t        dev;
76 
77 	uint32_t	psci_version;
78 	uint32_t	psci_fnids[PSCI_FN_MAX];
79 };
80 
81 #ifdef FDT
82 static int psci_v0_1_init(device_t dev, int default_version);
83 #endif
84 static int psci_v0_2_init(device_t dev, int default_version);
85 
86 struct psci_softc *psci_softc = NULL;
87 
88 #ifdef __arm__
89 #define	USE_ACPI	0
90 #define	USE_FDT		1
91 #elif defined(__aarch64__)
92 #define	USE_ACPI	(arm64_bus_method == ARM64_BUS_ACPI)
93 #define	USE_FDT		(arm64_bus_method == ARM64_BUS_FDT)
94 #else
95 #error Unknown architecture
96 #endif
97 
98 #ifdef FDT
99 struct psci_init_def {
100 	int		default_version;
101 	psci_initfn_t	psci_init;
102 };
103 
104 static struct psci_init_def psci_v1_0_init_def = {
105 	.default_version = (1 << 16) | 0,
106 	.psci_init = psci_v0_2_init
107 };
108 
109 static struct psci_init_def psci_v0_2_init_def = {
110 	.default_version = (0 << 16) | 2,
111 	.psci_init = psci_v0_2_init
112 };
113 
114 static struct psci_init_def psci_v0_1_init_def = {
115 	.default_version = (0 << 16) | 1,
116 	.psci_init = psci_v0_1_init
117 };
118 
119 static struct ofw_compat_data compat_data[] = {
120 	{"arm,psci-1.0",        (uintptr_t)&psci_v1_0_init_def},
121 	{"arm,psci-0.2",        (uintptr_t)&psci_v0_2_init_def},
122 	{"arm,psci",            (uintptr_t)&psci_v0_1_init_def},
123 	{NULL,                  0}
124 };
125 #endif
126 
127 static int psci_attach(device_t, psci_initfn_t, int);
128 static void psci_shutdown(void *, int);
129 
130 static int psci_find_callfn(psci_callfn_t *);
131 static int psci_def_callfn(register_t, register_t, register_t, register_t,
132 	register_t, register_t, register_t, register_t,
133 	struct arm_smccc_res *res);
134 
135 psci_callfn_t psci_callfn = psci_def_callfn;
136 
137 static void
138 psci_init(void *dummy)
139 {
140 	psci_callfn_t new_callfn;
141 
142 	if (psci_find_callfn(&new_callfn) != PSCI_RETVAL_SUCCESS) {
143 		printf("No PSCI/SMCCC call function found\n");
144 		return;
145 	}
146 
147 	psci_callfn = new_callfn;
148 }
149 /* This needs to be before cpu_mp at SI_SUB_CPU, SI_ORDER_THIRD */
150 SYSINIT(psci_start, SI_SUB_CPU, SI_ORDER_FIRST, psci_init, NULL);
151 
152 static int
153 psci_def_callfn(register_t a __unused, register_t b __unused,
154     register_t c __unused, register_t d __unused,
155     register_t e __unused, register_t f __unused,
156     register_t g __unused, register_t h __unused,
157     struct arm_smccc_res *res __unused)
158 {
159 
160 	panic("No PSCI/SMCCC call function set");
161 }
162 
163 #ifdef FDT
164 static int psci_fdt_probe(device_t dev);
165 static int psci_fdt_attach(device_t dev);
166 
167 static device_method_t psci_fdt_methods[] = {
168 	DEVMETHOD(device_probe,     psci_fdt_probe),
169 	DEVMETHOD(device_attach,    psci_fdt_attach),
170 
171 	DEVMETHOD_END
172 };
173 
174 static driver_t psci_fdt_driver = {
175 	"psci",
176 	psci_fdt_methods,
177 	sizeof(struct psci_softc),
178 };
179 
180 static devclass_t psci_fdt_devclass;
181 
182 EARLY_DRIVER_MODULE(psci, simplebus, psci_fdt_driver, psci_fdt_devclass, 0, 0,
183     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
184 EARLY_DRIVER_MODULE(psci, ofwbus, psci_fdt_driver, psci_fdt_devclass, 0, 0,
185     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
186 
187 static psci_callfn_t
188 psci_fdt_get_callfn(phandle_t node)
189 {
190 	char method[16];
191 
192 	if ((OF_getprop(node, "method", method, sizeof(method))) > 0) {
193 		if (strcmp(method, "hvc") == 0)
194 			return (arm_smccc_hvc);
195 		else if (strcmp(method, "smc") == 0)
196 			return (arm_smccc_smc);
197 		else
198 			printf("psci: PSCI conduit \"%s\" invalid\n", method);
199 	} else
200 		printf("psci: PSCI conduit not supplied in the device tree\n");
201 
202 	return (NULL);
203 }
204 
205 static int
206 psci_fdt_probe(device_t dev)
207 {
208 	const struct ofw_compat_data *ocd;
209 
210 	if (!ofw_bus_status_okay(dev))
211 		return (ENXIO);
212 
213 	ocd = ofw_bus_search_compatible(dev, compat_data);
214 	if (ocd->ocd_str == NULL)
215 		return (ENXIO);
216 
217 	device_set_desc(dev, "ARM Power State Co-ordination Interface Driver");
218 
219 	return (BUS_PROBE_SPECIFIC);
220 }
221 
222 static int
223 psci_fdt_attach(device_t dev)
224 {
225 	const struct ofw_compat_data *ocd;
226 	struct psci_init_def *psci_init_def;
227 
228 	ocd = ofw_bus_search_compatible(dev, compat_data);
229 	psci_init_def = (struct psci_init_def *)ocd->ocd_data;
230 
231 	return (psci_attach(dev, psci_init_def->psci_init,
232 	    psci_init_def->default_version));
233 }
234 #endif
235 
236 #ifdef DEV_ACPI
237 static void psci_acpi_identify(driver_t *, device_t);
238 static int psci_acpi_probe(device_t);
239 static int psci_acpi_attach(device_t);
240 
241 static device_method_t psci_acpi_methods[] = {
242 	/* Device interface */
243 	DEVMETHOD(device_identify,	psci_acpi_identify),
244 	DEVMETHOD(device_probe,		psci_acpi_probe),
245 	DEVMETHOD(device_attach,	psci_acpi_attach),
246 
247 	DEVMETHOD_END
248 };
249 
250 static driver_t psci_acpi_driver = {
251 	"psci",
252 	psci_acpi_methods,
253 	sizeof(struct psci_softc),
254 };
255 
256 static devclass_t psci_acpi_devclass;
257 
258 EARLY_DRIVER_MODULE(psci, acpi, psci_acpi_driver, psci_acpi_devclass, 0, 0,
259     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
260 
261 static int
262 psci_acpi_bootflags(void)
263 {
264 	ACPI_TABLE_FADT *fadt;
265 	vm_paddr_t physaddr;
266 	int flags;
267 
268 	physaddr = acpi_find_table(ACPI_SIG_FADT);
269 	if (physaddr == 0)
270 		return (0);
271 
272 	fadt = acpi_map_table(physaddr, ACPI_SIG_FADT);
273 	if (fadt == NULL) {
274 		printf("psci: Unable to map the FADT\n");
275 		return (0);
276 	}
277 
278 	flags = fadt->ArmBootFlags;
279 
280 	acpi_unmap_table(fadt);
281 	return (flags);
282 }
283 
284 static psci_callfn_t
285 psci_acpi_get_callfn(int flags)
286 {
287 
288 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) != 0) {
289 		if ((flags & ACPI_FADT_PSCI_USE_HVC) != 0)
290 			return (arm_smccc_hvc);
291 		else
292 			return (arm_smccc_smc);
293 	} else {
294 		printf("psci: PSCI conduit not supplied in the device tree\n");
295 	}
296 
297 	return (NULL);
298 }
299 
300 static void
301 psci_acpi_identify(driver_t *driver, device_t parent)
302 {
303 	device_t dev;
304 	int flags;
305 
306 	flags = psci_acpi_bootflags();
307 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) != 0) {
308 		dev = BUS_ADD_CHILD(parent,
309 		    BUS_PASS_CPU + BUS_PASS_ORDER_FIRST, "psci", -1);
310 
311 		if (dev != NULL)
312 			acpi_set_private(dev, (void *)(uintptr_t)flags);
313 	}
314 }
315 
316 static int
317 psci_acpi_probe(device_t dev)
318 {
319 	uintptr_t flags;
320 
321 	flags = (uintptr_t)acpi_get_private(dev);
322 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) == 0)
323 		return (ENXIO);
324 
325 	device_set_desc(dev, "ARM Power State Co-ordination Interface Driver");
326 	return (BUS_PROBE_SPECIFIC);
327 }
328 
329 static int
330 psci_acpi_attach(device_t dev)
331 {
332 
333 	return (psci_attach(dev, psci_v0_2_init, PSCI_RETVAL_NOT_SUPPORTED));
334 }
335 #endif
336 
337 static int
338 psci_attach(device_t dev, psci_initfn_t psci_init, int default_version)
339 {
340 	struct psci_softc *sc = device_get_softc(dev);
341 
342 	if (psci_softc != NULL)
343 		return (ENXIO);
344 
345 	KASSERT(psci_init != NULL, ("PSCI init function cannot be NULL"));
346 	if (psci_init(dev, default_version))
347 		return (ENXIO);
348 
349 	psci_softc = sc;
350 
351 	return (0);
352 }
353 
354 static int
355 _psci_get_version(struct psci_softc *sc)
356 {
357 	uint32_t fnid;
358 
359 	/* PSCI version wasn't supported in v0.1. */
360 	fnid = sc->psci_fnids[PSCI_FN_VERSION];
361 	if (fnid)
362 		return (psci_call(fnid, 0, 0, 0));
363 
364 	return (PSCI_RETVAL_NOT_SUPPORTED);
365 }
366 
367 int
368 psci_get_version(void)
369 {
370 
371 	if (psci_softc == NULL)
372 		return (PSCI_RETVAL_NOT_SUPPORTED);
373 	return (_psci_get_version(psci_softc));
374 }
375 
376 #ifdef FDT
377 static int
378 psci_fdt_callfn(psci_callfn_t *callfn)
379 {
380 	phandle_t node;
381 
382 	node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-0.2");
383 	if (node == 0) {
384 		node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-1.0");
385 		if (node == 0)
386 			return (PSCI_MISSING);
387 	}
388 
389 	*callfn = psci_fdt_get_callfn(node);
390 	return (0);
391 }
392 #endif
393 
394 #ifdef DEV_ACPI
395 static int
396 psci_acpi_callfn(psci_callfn_t *callfn)
397 {
398 	int flags;
399 
400 	flags = psci_acpi_bootflags();
401 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) == 0)
402 		return (PSCI_MISSING);
403 
404 	*callfn = psci_acpi_get_callfn(flags);
405 	return (0);
406 }
407 #endif
408 
409 static int
410 psci_find_callfn(psci_callfn_t *callfn)
411 {
412 	int error;
413 
414 	*callfn = NULL;
415 #ifdef FDT
416 	if (USE_FDT) {
417 		error = psci_fdt_callfn(callfn);
418 		if (error != 0)
419 			return (error);
420 	}
421 #endif
422 #ifdef DEV_ACPI
423 	if (*callfn == NULL && USE_ACPI) {
424 		error = psci_acpi_callfn(callfn);
425 		if (error != 0)
426 			return (error);
427 	}
428 #endif
429 
430 	if (*callfn == NULL)
431 		return (PSCI_MISSING);
432 
433 	return (PSCI_RETVAL_SUCCESS);
434 }
435 
436 int32_t
437 psci_features(uint32_t psci_func_id)
438 {
439 
440 	if (psci_softc == NULL)
441 		return (PSCI_RETVAL_NOT_SUPPORTED);
442 
443 	/* The feature flags were added to PSCI 1.0 */
444 	if (PSCI_VER_MAJOR(psci_softc->psci_version) < 1)
445 		return (PSCI_RETVAL_NOT_SUPPORTED);
446 
447 	return (psci_call(PSCI_FNID_FEATURES, psci_func_id, 0, 0));
448 }
449 
450 int
451 psci_cpu_on(unsigned long cpu, unsigned long entry, unsigned long context_id)
452 {
453 	uint32_t fnid;
454 
455 	fnid = PSCI_FNID_CPU_ON;
456 	if (psci_softc != NULL)
457 		fnid = psci_softc->psci_fnids[PSCI_FN_CPU_ON];
458 
459 	/* PSCI v0.1 and v0.2 both support cpu_on. */
460 	return (psci_call(fnid, cpu, entry, context_id));
461 }
462 
463 static void
464 psci_shutdown(void *xsc, int howto)
465 {
466 	uint32_t fn = 0;
467 
468 	if (psci_softc == NULL)
469 		return;
470 
471 	/* PSCI system_off and system_reset werent't supported in v0.1. */
472 	if ((howto & RB_POWEROFF) != 0)
473 		fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_OFF];
474 	else if ((howto & RB_HALT) == 0)
475 		fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_RESET];
476 
477 	if (fn)
478 		psci_call(fn, 0, 0, 0);
479 
480 	/* System reset and off do not return. */
481 }
482 
483 void
484 psci_reset(void)
485 {
486 
487 	psci_shutdown(NULL, 0);
488 }
489 
490 #ifdef FDT
491 /* Only support PSCI 0.1 on FDT */
492 static int
493 psci_v0_1_init(device_t dev, int default_version __unused)
494 {
495 	struct psci_softc *sc = device_get_softc(dev);
496 	int psci_fn;
497 	uint32_t psci_fnid;
498 	phandle_t node;
499 	int len;
500 
501 	/* Zero out the function ID table - Is this needed ? */
502 	for (psci_fn = PSCI_FN_VERSION, psci_fnid = PSCI_FNID_VERSION;
503 	    psci_fn < PSCI_FN_MAX; psci_fn++, psci_fnid++)
504 		sc->psci_fnids[psci_fn] = 0;
505 
506 	/* PSCI v0.1 doesn't specify function IDs. Get them from DT */
507 	node = ofw_bus_get_node(dev);
508 
509 	if ((len = OF_getproplen(node, "cpu_suspend")) > 0) {
510 		OF_getencprop(node, "cpu_suspend", &psci_fnid, len);
511 		sc->psci_fnids[PSCI_FN_CPU_SUSPEND] = psci_fnid;
512 	}
513 
514 	if ((len = OF_getproplen(node, "cpu_on")) > 0) {
515 		OF_getencprop(node, "cpu_on", &psci_fnid, len);
516 		sc->psci_fnids[PSCI_FN_CPU_ON] = psci_fnid;
517 	}
518 
519 	if ((len = OF_getproplen(node, "cpu_off")) > 0) {
520 		OF_getencprop(node, "cpu_off", &psci_fnid, len);
521 		sc->psci_fnids[PSCI_FN_CPU_OFF] = psci_fnid;
522 	}
523 
524 	if ((len = OF_getproplen(node, "migrate")) > 0) {
525 		OF_getencprop(node, "migrate", &psci_fnid, len);
526 		sc->psci_fnids[PSCI_FN_MIGRATE] = psci_fnid;
527 	}
528 
529 	sc->psci_version = (0 << 16) | 1;
530 	if (bootverbose)
531 		device_printf(dev, "PSCI version 0.1 available\n");
532 
533 	return(0);
534 }
535 #endif
536 
537 static int
538 psci_v0_2_init(device_t dev, int default_version)
539 {
540 	struct psci_softc *sc = device_get_softc(dev);
541 	int version;
542 
543 	/* PSCI v0.2 specifies explicit function IDs. */
544 	sc->psci_fnids[PSCI_FN_VERSION]		    = PSCI_FNID_VERSION;
545 	sc->psci_fnids[PSCI_FN_CPU_SUSPEND]	    = PSCI_FNID_CPU_SUSPEND;
546 	sc->psci_fnids[PSCI_FN_CPU_OFF]		    = PSCI_FNID_CPU_OFF;
547 	sc->psci_fnids[PSCI_FN_CPU_ON]		    = PSCI_FNID_CPU_ON;
548 	sc->psci_fnids[PSCI_FN_AFFINITY_INFO]	    = PSCI_FNID_AFFINITY_INFO;
549 	sc->psci_fnids[PSCI_FN_MIGRATE]		    = PSCI_FNID_MIGRATE;
550 	sc->psci_fnids[PSCI_FN_MIGRATE_INFO_TYPE]   = PSCI_FNID_MIGRATE_INFO_TYPE;
551 	sc->psci_fnids[PSCI_FN_MIGRATE_INFO_UP_CPU] = PSCI_FNID_MIGRATE_INFO_UP_CPU;
552 	sc->psci_fnids[PSCI_FN_SYSTEM_OFF]	    = PSCI_FNID_SYSTEM_OFF;
553 	sc->psci_fnids[PSCI_FN_SYSTEM_RESET]	    = PSCI_FNID_SYSTEM_RESET;
554 
555 	version = _psci_get_version(sc);
556 
557 	/*
558 	 * U-Boot PSCI implementation doesn't have psci_get_version()
559 	 * method implemented for many boards. In this case, use the version
560 	 * readed from FDT as fallback. No fallback method for ACPI.
561 	 */
562 	if (version == PSCI_RETVAL_NOT_SUPPORTED) {
563 		if (default_version == PSCI_RETVAL_NOT_SUPPORTED)
564 			return (1);
565 
566 		version = default_version;
567 		printf("PSCI get_version() function is not implemented, "
568 		    " assuming v%d.%d\n", PSCI_VER_MAJOR(version),
569 		    PSCI_VER_MINOR(version));
570 	}
571 
572 	sc->psci_version = version;
573 	if ((PSCI_VER_MAJOR(version) == 0 && PSCI_VER_MINOR(version) == 2) ||
574 	    PSCI_VER_MAJOR(version) == 1) {
575 		if (bootverbose)
576 			device_printf(dev, "PSCI version 0.2 compatible\n");
577 
578 		/*
579 		 * We only register this for v0.2 since v0.1 doesn't support
580 		 * system_reset.
581 		 */
582 		EVENTHANDLER_REGISTER(shutdown_final, psci_shutdown, sc,
583 		    SHUTDOWN_PRI_LAST);
584 
585 		return (0);
586 	}
587 
588 	device_printf(dev, "PSCI version number mismatched with DT\n");
589 	return (1);
590 }
591